Tuesday, March 27, 2007

Top tiny creations

A recent story about 'microscopic alphabet soup' created at UCLA got us thinking about all the quirky ways researchers have chosen to demonstrate new micro, nano-scale technology.

Here's a quick list:

1. The UCLA team wanted to show how accurately they could sculpt tiny particles produced in large numbers. So they chose to make the whole alphabet - along with some nice pics showing how these can be manipulated to spell, you guessed it, UCLA. The scale bar in the image to the left is three microns long.

2. Giving props to your own institution is naturally a common theme. One of the most famous examples is these 5nm xenon letters created by Donald Eigler and Erhard Schweizer to show off their new scanning tunnelling microscope way back in 1990. A tiny man made from carbon monoxide molecules was also produced at IBM.

3. Ken Teo of Cambridge University sent me this great image of the New Scientist logo written in carbon nanotubes a while ago. They're 50 nanometres in diameter and 1.5 microns long. The entire logo, from N to t, is 120 microns. Ken has also discovered that forests of nanotubes can be even less sticky than teflon.

4. Researchers at Japanese firm Hitachi decided to make a statement in 1991 when they wrote the message 'Peace 91 HCRL' by knocking sulphur atoms one by one from the surface of a molybdenum disulphide crystal. Not only were the 1.5nm letters smaller than IBM's, the process took place at room temperature instead of minus 263°C. According to Shojiro Asai, deputy general manager of the lab, the researchers who did the work chose the message. "We should hope for peace in 1991 because of the Gulf situation," he said. But they were also sure to put in the initials of the Hitachi Central Research Laboratory. To find out more and for help locating the letters try this link.

5. In 1997, a PhD student at the Cornell Nanofabrication Facility in New York made a "nanoguitar" that's just 10 microns long. It was carved from a single silicon crystal using an electron beam. Each string is about 100 atoms wide and they were plucked using an atomic force microscope. In 2003, he made a fancier version - more pictures and a few recordings of it being played.

6. In August 2005 this badger was made from nanotubes by graduate students from the University of Wisconsin-Madison, US. Their rendering of the university's mascot is about 15 microns across - you could probably get 9,000 of them onto the head of a single pin.

8. And finally... the world's smallest advert. It was positioned on a bee's leg by scientists at the Rutherford Appleton Laboratory, UK. They used vapour deposition to produce the gold advert for the Guiness Book of Records website in 2000, and then moved it to its headline-grabbing location. It was just 100 microns wide.

Of course these are the images that got released to the press. In labs around the world people must have used their bleeding-edge technologies to make structures just to impress their friends. I wonder how many scientists' significant others have received nano-Valentines on Feb 14th? And how can I get one next year?

also nice tiny artwork:http://www.laser-zentrum-hannover.de/en/fields_of_work/material_processing/img/nano-venus.jpgunfortunatly only in german:http://www.laser-zentrum-hannover.de/de/kompetenzen/laserentwicklung/nanotechnologie/2pp.php

As a regular reader of your blog, I wanted to thank you for showcasing the nanoguitar. I just wanted to add (and correct a little) to what you said in #5. The first nanoguitar (made by Dustin W. Carr in 1997, in Harold Craighead's group) was indeed carved out of single-crystal silicon layer but it's only the first "writing" in a layer over that silicon that is done with electron beam lithography. It's made just like silicon computer chips are made. That guitar was, unfortunately, not played.

Its younger cousin, the playable nanoguitar, was made by me (when I was a graduate student in the same research group) in 2002, in collaboration with my colleagues Keith Aubin and Jingqing Huang. That guitar was larger and it was "played" using laser light. Both were made as educational outreach projects to demonstrate how small we can make various objects and about the special dynamics that occurs at the micro and nanoscale where small heating induced by light can induce vibrations.